<?php
/* vim: set expandtab sw=4 ts=4 sts=4: */
/**
 * function library for handling table indexes
 *
 * @version $Id: tbl_indexes.lib.php 10240 2007-04-01 11:02:46Z cybot_tm $
 */

/**
 * Return a list of all index types
 *
 * @access  public
 * @return  array	   Index types
 * @author  Garvin Hicking (pma@supergarv.de)
 */
function PMA_get_indextypes()
{
	return array(
		'PRIMARY',
		'INDEX',
		'UNIQUE',
		'FULLTEXT',
	);
}

/**
 * Function to get all index information from a certain table
 *
 * @uses	PMA_DBI_fetch_result()
 * @uses	PMA_backquote()
 * @param   string  $tbl_name   Table name to ftech indexes from
 * @param   string  $err_url_0  Error URL
 *
 * @access  public
 * @return  array	   Index keys
 */
function PMA_get_indexes($tbl_name, $err_url_0 = '')
{
	return PMA_DBI_fetch_result('SHOW KEYS FROM ' . PMA_backquote($tbl_name));
}

/**
 * Function to check over array of indexes and look for common problems
 *
 * @uses	$GLOBALS['strIndexesSeemEqual']
 * @uses	PMA_get_indexes()
 * @uses	is_string()
 * @uses	is_array()
 * @uses	count()
 * @uses	array_pop()
 * @uses	reset()
 * @uses	current()
 * @access  public
 * @param   mixed	   array of indexes from PMA_get_indexes()
 *					  or name of table
 * @return  string	  Output HTML
 */
function PMA_check_indexes($idx_collection)
{
	if (is_string($idx_collection)) {
		$idx_collection = PMA_get_indexes($idx_collection);
	}

	// count($idx_collection) < 2:
	//   there is no need to check if there less than two indexes
	if (! is_array($idx_collection) || count($idx_collection) < 2) {
		return false;
	}

	$indexes = array();
	foreach ($idx_collection as $index_field) {
		$indexes[$index_field['Key_name']][$index_field['Column_name']]
			= $index_field;
	}

	$output  = '';

	// remove last index from stack and ...
	while ($while_index = array_pop($indexes)) {
		// ... compare with every remaining index in stack
		foreach ($indexes as $each_index_name => $each_index) {
			if (count($while_index) !== count($each_index)) {
				// number of fields are not equal
				continue;
			}

			// compare some key elements of every column in this two indexes
			foreach ($each_index as $col_name => $each_index_column) {
				if (! isset($while_index[$col_name])
				 // the position
				 || $while_index[$col_name]['Seq_in_index'] !== $each_index_column['Seq_in_index']
				 // the order, ASC or DESC
				 || $while_index[$col_name]['Collation']	!== $each_index_column['Collation']
				 // the length
				 || $while_index[$col_name]['Sub_part']	 !== $each_index_column['Sub_part']
				 // BTREE or HASH
				 || $while_index[$col_name]['Index_type']   !== $each_index_column['Index_type']) {
					continue 2;
				}
			}

			// did not find any difference
			// so it makes no sense to have this two equal indexes

			// use first column from index to fetch index name
			reset($while_index);
			$first_column = current($while_index);

			$output .= '<div class="warning">';
			$output .= $GLOBALS['strIndexesSeemEqual'] . ' ';
			$output .= $each_index_name . ', ' . $first_column['Key_name'];
			$output .= '</div>';

			// there is no need to check any further indexes if we have already
			// found that this one has a duplicate
			continue 2;
		}
	}

	if ($output) {
		$output = '<tr><td colspan=7">' . $output . '</td></tr>';
	}

	return $output;
}

/**
 * Loop array of returned index keys and extract key information to
 * seperate arrays. Those arrays are passed by reference.
 *
 * @param   array	   Referenced Array of indexes
 * @param   array	   Referenced return array
 * @param   array	   Referenced return array
 * @param   array	   Referenced return array
 *
 * @access  public
 * @return  boolean	 void
 * @author  Garvin Hicking (pma@supergarv.de)
 */
function PMA_extract_indexes(&$ret_keys, &$indexes, &$indexes_info, &$indexes_data)
{
	if (! is_array($ret_keys)) {
		return false;
	}

	$prev_index   = '';
	foreach ($ret_keys as $row) {
		if ($row['Key_name'] != $prev_index){
			$indexes[]  = $row['Key_name'];
			$prev_index = $row['Key_name'];
		}

		$indexes_info[$row['Key_name']]['Sequences'][]	 = $row['Seq_in_index'];
		$indexes_info[$row['Key_name']]['Non_unique']	  = $row['Non_unique'];

		if (isset($row['Cardinality'])) {
			$indexes_info[$row['Key_name']]['Cardinality'] = $row['Cardinality'];
		}

		//	I don't know what does following column mean....
		//	$indexes_info[$row['Key_name']]['Packed']		  = $row['Packed'];
		$indexes_info[$row['Key_name']]['Comment']		 = (isset($row['Comment']))
														   ? $row['Comment']
														   : '';
		$indexes_info[$row['Key_name']]['Index_type']	  = (isset($row['Index_type']))
														   ? $row['Index_type']
														   : '';

		$indexes_data[$row['Key_name']][$row['Seq_in_index']]['Column_name']  = $row['Column_name'];
		if (isset($row['Sub_part'])) {
			$indexes_data[$row['Key_name']][$row['Seq_in_index']]['Sub_part'] = $row['Sub_part'];
		}
	} // end while

	return true;
}

/**
 * Show index data and prepare returned collection array for index
 * key checks.
 *
 * @param   string	  $table		  The tablename
 * @param   array	   $indexes		Referenced Array of indexes
 * @param   array	   $indexes_info   Referenced info array
 * @param   array	   $indexes_data   Referenced data array
 * @param   boolean	 $display_html   Output HTML code, or just return collection array?
 * @param   boolean	 $print_mode
 * @access  public
 * @return  array	   Index collection array
 * @author  Garvin Hicking (pma@supergarv.de)
 */
function PMA_show_indexes($table, &$indexes, &$indexes_info, &$indexes_data,
	$display_html = true, $print_mode = false)
{
	$idx_collection = array();
	$odd_row = true;
	foreach ($indexes as $index_name) {
		if ($display_html) {
			$row_span = ' rowspan="' . count($indexes_info[$index_name]['Sequences']) . '" ';

			echo '		<tr class="' . ($odd_row ? 'odd' : 'even') . '">' . "\n";
			echo '			<th ' . $row_span . '>' . "\n"
			   . '				' . htmlspecialchars($index_name) . "\n"
			   . '			</th>' . "\n";
		}

		if ((PMA_MYSQL_INT_VERSION < 40002 && $indexes_info[$index_name]['Comment'] == 'FULLTEXT')
			|| (PMA_MYSQL_INT_VERSION >= 40002 && $indexes_info[$index_name]['Index_type'] == 'FULLTEXT')) {
			$index_type = 'FULLTEXT';
		} elseif ($index_name == 'PRIMARY') {
			$index_type = 'PRIMARY';
		} elseif ($indexes_info[$index_name]['Non_unique'] == '0') {
			$index_type = 'UNIQUE';
		} else {
			$index_type = 'INDEX';
		}

		if ($display_html) {
			echo '			<td ' . $row_span . '>' . "\n"
			   . '				' . $index_type . '</td>' . "\n";

			echo '			<td ' . $row_span . ' align="right">' . "\n"
			   . '				' . (isset($indexes_info[$index_name]['Cardinality']) ? $indexes_info[$index_name]['Cardinality'] : $GLOBALS['strNone']) . '&nbsp;' . "\n"
			   . '			</td>' . "\n";

			if (!$print_mode) {
				echo '			<td ' . $row_span . '>' . "\n"
				   . '				<a href="tbl_indexes.php?'
				   . $GLOBALS['url_query'] . '&amp;index=' . urlencode($index_name)
				   . '">' . $GLOBALS['edit_link_text'] . '</a>' . "\n"
				   . '			</td>' . "\n";

				if ($index_name == 'PRIMARY') {
					$local_query = urlencode('ALTER TABLE ' . PMA_backquote($table) . ' DROP PRIMARY KEY');
					$js_msg	  = 'ALTER TABLE ' . PMA_jsFormat($table) . ' DROP PRIMARY KEY';
					$zero_rows   = urlencode($GLOBALS['strPrimaryKeyHasBeenDropped']);
				} else {
					$local_query = urlencode('ALTER TABLE ' . PMA_backquote($table) . ' DROP INDEX ' . PMA_backquote($index_name));
					$js_msg	  = 'ALTER TABLE ' . PMA_jsFormat($table) . ' DROP INDEX ' . PMA_jsFormat($index_name);
					$zero_rows   = urlencode(sprintf($GLOBALS['strIndexHasBeenDropped'], htmlspecialchars($index_name)));
				}

				echo '			<td ' . $row_span . '>' . "\n"
				   . '				<a href="sql.php?' . $GLOBALS['url_query']
				   . '&amp;sql_query=' . $local_query . '&amp;zero_rows='
				   . $zero_rows . '" onclick="return confirmLink(this, \''
				   . $js_msg . '\')">' . $GLOBALS['drop_link_text']  . '</a>' . "\n"
				   . '			</td>' . "\n";
			}
		}

		foreach ($indexes_info[$index_name]['Sequences'] AS $row_no => $seq_index) {
			$col_name = $indexes_data[$index_name][$seq_index]['Column_name'];
			if ($row_no == 0) {
				if (isset($idx_collection[$index_type][$col_name])) {
					$idx_collection[$index_type][$col_name]++;
				} else {
					$idx_collection[$index_type][$col_name] = 1;
				}

				if (isset($idx_collection['ALL'][$col_name])) {
					$idx_collection['ALL'][$col_name]++;
				} else {
					$idx_collection['ALL'][$col_name] = 1;
				}
			}

			if ($display_html) {
				if ($row_no > 0) {
					echo '		<tr class="' . ($odd_row ? 'odd' : 'even') . '">' . "\n";
				}

				if (isset($indexes_data[$index_name][$seq_index]['Sub_part'])
				 && strlen($indexes_data[$index_name][$seq_index]['Sub_part'])) {
					echo '			<td>' . $col_name . '</td>' . "\n";
					echo '			<td align="right">' . "\n"
					   . '				' . $indexes_data[$index_name][$seq_index]['Sub_part'] . "\n"
					   . '			</td>' . "\n";
					echo '		</tr>' . "\n";
				} else {
					echo '			<td colspan="2">' . "\n"
					   . '				' . htmlspecialchars($col_name) . "\n"
					   . '			</td>' . "\n";
					echo '		</tr>' . "\n";
				}
			}
		} // end foreach $indexes_info[$index_name]['Sequences']

		$odd_row = ! $odd_row;
	} // end while

	return $idx_collection;
}

?>
